lib/tevent/tevent_req.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Infrastructure for async requests
   4    Copyright (C) Volker Lendecke 2008
   5    Copyright (C) Stefan Metzmacher 2009
   6
   7      ** NOTE! The following LGPL license applies to the tevent
   8      ** library. This does NOT imply that all of Samba is released
   9      ** under the LGPL
  10
  11    This library is free software; you can redistribute it and/or
  12    modify it under the terms of the GNU Lesser General Public
  13    License as published by the Free Software Foundation; either
  14    version 3 of the License, or (at your option) any later version.
  15
  16    This library is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19    Lesser General Public License for more details.
  20
  21    You should have received a copy of the GNU Lesser General Public
  22    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  23 */
  24
  25 #include "replace.h"
  26 #include "tevent.h"
  27 #include "tevent_internal.h"
  28 #include "tevent_util.h"
  29
  30 char *tevent_req_default_print(struct tevent_req *req, TALLOC_CTX *mem_ctx)
  31 {
  32         return talloc_asprintf(mem_ctx,
  33                                "tevent_req[%p/%s]: state[%d] error[%lld (0x%llX)] "
  34                                " state[%s (%p)] timer[%p]",
  35                                req, req->internal.create_location,
  36                                req->internal.state,
  37                                (unsigned long long)req->internal.error,
  38                                (unsigned long long)req->internal.error,
  39                                talloc_get_name(req->data),
  40                                req->data,
  41                                req->internal.timer
  42                                );
  43 }
  44
  45 char *tevent_req_print(TALLOC_CTX *mem_ctx, struct tevent_req *req)
  46 {
  47         if (!req->private_print) {
  48                 return tevent_req_default_print(req, mem_ctx);
  49         }
  50
  51         return req->private_print(req, mem_ctx);
  52 }
  53
  54 struct tevent_req *_tevent_req_create(TALLOC_CTX *mem_ctx,
  55                                     void *pdata,
  56                                     size_t data_size,
  57                                     const char *type,
  58                                     const char *location)
  59 {
  60         struct tevent_req *req;
  61         void **ppdata = (void **)pdata;
  62         void *data;
  63
  64         req = talloc_zero(mem_ctx, struct tevent_req);
  65         if (req == NULL) {
  66                 return NULL;
  67         }
  68         req->internal.private_type      = type;
  69         req->internal.create_location   = location;
  70         req->internal.finish_location   = NULL;
  71         req->internal.state             = TEVENT_REQ_IN_PROGRESS;
  72         req->internal.trigger           = tevent_create_immediate(req);
  73         if (!req->internal.trigger) {
  74                 talloc_free(req);
  75                 return NULL;
  76         }
  77
  78         data = talloc_zero_size(req, data_size);
  79         if (data == NULL) {
  80                 talloc_free(req);
  81                 return NULL;
  82         }
  83         talloc_set_name_const(data, type);
  84
  85         req->data = data;
  86
  87         *ppdata = data;
  88         return req;
  89 }
  90
  91 void _tevent_req_notify_callback(struct tevent_req *req, const char *location)
  92 {
  93         req->internal.finish_location = location;
  94         if (req->async.fn != NULL) {
  95                 req->async.fn(req);
  96         }
  97 }
  98
  99 static void tevent_req_finish(struct tevent_req *req,
 100                               enum tevent_req_state state,
 101                               const char *location)
 102 {
 103         req->internal.state = state;
 104         _tevent_req_notify_callback(req, location);
 105 }
 106
 107 void _tevent_req_done(struct tevent_req *req,
 108                       const char *location)
 109 {
 110         tevent_req_finish(req, TEVENT_REQ_DONE, location);
 111 }
 112
 113 bool _tevent_req_error(struct tevent_req *req,
 114                        uint64_t error,
 115                        const char *location)
 116 {
 117         if (error == 0) {
 118                 return false;
 119         }
 120
 121         req->internal.error = error;
 122         tevent_req_finish(req, TEVENT_REQ_USER_ERROR, location);
 123         return true;
 124 }
 125
 126 void _tevent_req_oom(struct tevent_req *req, const char *location)
 127 {
 128         tevent_req_finish(req, TEVENT_REQ_NO_MEMORY, location);
 129 }
 130
 131 bool _tevent_req_nomem(const void *p,
 132                        struct tevent_req *req,
 133                        const char *location)
 134 {
 135         if (p != NULL) {
 136                 return false;
 137         }
 138         _tevent_req_oom(req, location);
 139         return true;
 140 }
 141
 142 /**
 143  * @internal
 144  *
 145  * @brief Immediate event callback.
 146  *
 147  * @param[in]  ev       The event context to use.
 148  *
 149  * @param[in]  im       The immediate event.
 150  *
 151  * @param[in]  priv     The async request to be finished.
 152  */
 153 static void tevent_req_trigger(struct tevent_context *ev,
 154                                struct tevent_immediate *im,
 155                                void *private_data)
 156 {
 157         struct tevent_req *req = talloc_get_type(private_data,
 158                                  struct tevent_req);
 159
 160         tevent_req_finish(req, req->internal.state,
 161                           req->internal.finish_location);
 162 }
 163
 164 struct tevent_req *tevent_req_post(struct tevent_req *req,
 165                                    struct tevent_context *ev)
 166 {
 167         tevent_schedule_immediate(req->internal.trigger,
 168                                   ev, tevent_req_trigger, req);
 169         return req;
 170 }
 171
 172 bool tevent_req_is_in_progress(struct tevent_req *req)
 173 {
 174         if (req->internal.state == TEVENT_REQ_IN_PROGRESS) {
 175                 return true;
 176         }
 177
 178         return false;
 179 }
 180
 181 void tevent_req_received(struct tevent_req *req)
 182 {
 183         TALLOC_FREE(req->data);
 184         req->private_print = NULL;
 185
 186         TALLOC_FREE(req->internal.trigger);
 187         TALLOC_FREE(req->internal.timer);
 188
 189         req->internal.state = TEVENT_REQ_RECEIVED;
 190 }
 191
 192 bool tevent_req_poll(struct tevent_req *req,
 193                      struct tevent_context *ev)
 194 {
 195         while (tevent_req_is_in_progress(req)) {
 196                 int ret;
 197
 198                 ret = tevent_loop_once(ev);
 199                 if (ret != 0) {
 200                         return false;
 201                 }
 202         }
 203
 204         return true;
 205 }
 206
 207 bool tevent_req_is_error(struct tevent_req *req, enum tevent_req_state *state,
 208                         uint64_t *error)
 209 {
 210         if (req->internal.state == TEVENT_REQ_DONE) {
 211                 return false;
 212         }
 213         if (req->internal.state == TEVENT_REQ_USER_ERROR) {
 214                 *error = req->internal.error;
 215         }
 216         *state = req->internal.state;
 217         return true;
 218 }
 219
 220 static void tevent_req_timedout(struct tevent_context *ev,
 221                                struct tevent_timer *te,
 222                                struct timeval now,
 223                                void *private_data)
 224 {
 225         struct tevent_req *req = talloc_get_type(private_data,
 226                                  struct tevent_req);
 227
 228         TALLOC_FREE(req->internal.timer);
 229
 230         tevent_req_finish(req, TEVENT_REQ_TIMED_OUT, __FUNCTION__);
 231 }
 232
 233 bool tevent_req_set_endtime(struct tevent_req *req,
 234                             struct tevent_context *ev,
 235                             struct timeval endtime)
 236 {
 237         TALLOC_FREE(req->internal.timer);
 238
 239         req->internal.timer = tevent_add_timer(ev, req, endtime,
 240                                                tevent_req_timedout,
 241                                                req);
 242         if (tevent_req_nomem(req->internal.timer, req)) {
 243                 return false;
 244         }
 245
 246         return true;
 247 }
 248
 249 void tevent_req_set_callback(struct tevent_req *req, tevent_req_fn fn, void *pvt)
 250 {
 251         req->async.fn = fn;
 252         req->async.private_data = pvt;
 253 }
 254
 255 void *_tevent_req_callback_data(struct tevent_req *req)
 256 {
 257         return req->async.private_data;
 258 }
 259
 260 void *_tevent_req_data(struct tevent_req *req)
 261 {
 262         return req->data;
 263 }
 264
 265 void tevent_req_set_print_fn(struct tevent_req *req, tevent_req_print_fn fn)
 266 {
 267         req->private_print = fn;
 268 }
 269
 270 void tevent_req_set_cancel_fn(struct tevent_req *req, tevent_req_cancel_fn fn)
 271 {
 272         req->private_cancel = fn;
 273 }
 274
 275 bool _tevent_req_cancel(struct tevent_req *req, const char *location)
 276 {
 277         if (req->private_cancel == NULL) {
 278                 return false;
 279         }
 280
 281         return req->private_cancel(req);
 282 }